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Add locations for parser #3186

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Add locations for parser #3186

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6 changes: 6 additions & 0 deletions docs/parser.md
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Expand Up @@ -34,6 +34,7 @@ mind. When in doubt, use `.parse()`.

| Version | Changes |
| --------- | -------------------------------------------------- |
| `v8.0.0` | Added `locations` |
| `v7.28.0` | Added `sourceType: "commonjs"` |
| `v7.27.0` | Added `allowYieldOutsideFunction` |
| `v7.26.0` | Added `startIndex` |
Expand Down Expand Up @@ -94,6 +95,11 @@ mind. When in doubt, use `.parse()`.
The resulting AST will have an `errors` property representing an array of all the parsing errors.
Note that even when this option is enabled, `@babel/parser` could throw for unrecoverable errors.

- **locations**: Can be one of `true`, `false` or `packed`.
`true` is the default and will add a `loc` property to each node, which is an object with `start` and `end` properties, which are objects containing `line` and `column` numbers.
When set to `false`, the "loc" property will not be included in the output AST.
When set to `packed`, the `parse` function will return an `Uint32Array` of the form (`[line1, column1, line2, column2, ...]`). You can access the line and column numbers of a node with `locData[node.start * 2]` for the starting line, `locData[node.start * 2 + 1]` for the starting column, `locData[node.end * 2]` for the ending line and `locData[node.end * 2 + 1]` for the ending column.
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@nicolo-ribaudo nicolo-ribaudo Mar 13, 2026

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Can you add an example for packed? Do we not also return an AST?


- **plugins**: Array containing the plugins that you want to enable.

- **sourceType**: Indicate the mode the code should be parsed in. Can be
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